The rotator cuff muscles work as a unit. They help to stabilise the shoulder joint and also help with shoulder joint movement. These things seem to come in packages of four, as there are also four tendons of the rotator cuff muscles that join together to form one larger tendon, called the rotator cuff tendon (not a very imaginative name if you ask me). This tendon attaches to the head of the bony surface at the top of the upper arm bone, which is called quite sarcastically the humerus. The rotator cuff tendon passes through a space underneath the acromion of the scapula, called the subacromial space (oh come on, was it trainee day at the naming department????).
Rotator cuff injuries occur most often in those who repeatedly perform overhead motions in their jobs or sports. Examples include painters, carpenters, and people who play baseball or tennis. It can also develop after lifting or pulling something awkwardly, or reaching to get something heavy off a top shelf. Using your arm to break a fall or falling on your arm can do it. Some people develop bone spurs, an overgrowth of bone, on the top of the shoulder blade that protrudes over the rotator cuff. Repetitive stress of any kind can cause inflammation and eventual tearing. that doesn't sound to good, and it's not, as it can cause irritation and damage.
The risk of rotator cuff injury also increases with age.
It's common to recover from a rotator cuff injury with physical therapy exercises that improve flexibility and strength of the muscles surrounding the shoulder joint. Most people exercise the front muscles of the chest, shoulder and upper arm, but it is equally important to strengthen the muscles in the back of the shoulder and around the shoulder blade to optimize shoulder muscle balance. Severe rotator cuff injuries, involving complete tears of the muscle or tendon, may require surgical repair. Other treatments include: rest, heat or cold depending on stiffness (heat) or inflammation (cold), medicines (ibuprophen for example), ultrasound, massage, and acupuncture. Cortisone injection is another option, but that's a pretty last resort, before surgery.
So I am visiting a physiotherapist who performs massage, acupuncture and ultrasound as needed. I have a few exercises that get tweaked every two weeks or so, and I ice the shoulder after I exercise. I also take ibuprophen when it is sore, but not on an empty stomach as ibuprophen can cause stomach pain in some people. I am also having to modify my pilates and yoga classes so that I don't overdo arm and shoulder work, and I have left off swimming for the time being, focussing on walking and biking instead. It's a slow, painful, frustrating business, but I am seeing modest improvement.